Instrument holder



O. H. PIEPER Feb. l0, 1931.

INSTRUMENT HOLDER Original Filed April 2, 1926 4 Y fr .f

Patented Fel. 10, 17931 'UNITED STATES gPA.'rliNT OFFICE om PIEPEB, 0l'ROCHESTER, NEW YORK 'INSTRUMENT HOLDER Application illedApril ,2, 1926,Serial lo. 99,286. ARenewed December 16, 1929.

tachedfto the instrument handles by ordi-` nary screw threads, and insome cases by a bayonet joint. The objections to these arrangements arerthat too much time is consumed 1n turning the bases of the tools orinstruments into or out`of the handle or grip ofthe holder. Anotherdisadvantage and objection is that the instrument or tool will alwayshave the same position relative to the electric controlling switchbutton, and this is not always most desirable orfconvenient in themanipulation of the holder.

The object'of'the invention is therefore to overcome all theseobjections by providing improved holding arrangement or joint betweenthe instrument or tool and the grip or handle part which will permit theinstrument or tool to be quickly inserted or removed and which will alsopermit the instrument or tool to be easily turned to the desiredposition relative 'to the switch button while the instrument is beingused. This is accomplished by means of a split collet in the mouth ofthe handle, and a tapered shank or plug on the base of the instrument ortool. The structure will be more fully understood by reference to thedrawings, on which,

Figure 1 is a side elevational view of a dental holder and tool;

Fig. 2 is an enlarged sectional view on plane 2--2 of Figure 1;

Fig. 3 is an enlarged side elevational view of the split collet;

Fig. 4 is an inner end view of the collet;

Fig. 5 is a side elevational view of the instrument base; and

Fig. 6 is a sectional view on plane 6 6, Figure 2.

In the structure shown the tubular handle or grip part 10 has the sleeve1l which supports the contact button 12 which is readily slidable in thesleeve and through the slot 13 in the handle, and the longitudinalsliding motion of the tubular handle is limited by the extent of theslot 13. Within the tubular handle is circuit controlling mechanismcomprising the supporting body 14' ofy insulating material and theterminal springs 15 and 16 'mounted thereon, the support being heldwithin the tube by a screw 17 and the terminal springs connectingwith'the circuit `cord 18 which extends through the plug 19"'at the endof the tubular handle.

In the from end 0f the banda, tube is in-` ible segments 22 by the slits23.

y into the collet C. Theinner end of the shank which engages in theskirt section of the collet is preferablycylindrical and inI order-thatthe spring sections of the skirt may clamp the shank end the end may beof slightly larger diameter than the skirt or the skirt can be radiallycontracted after being slitted. The outer end of the shank is preferablytapered slightly and the outer end of the collet is tapered tocorrespond. The object of this is to'save making an extremely accurate tbetween the twoparts which would be necessary if both parts werestraight. Ordinarily, the slit skirt end of the collet will exerteflicient clamping action on the shank to lock the instrument or toolagainst displacementduring use. The tapered surfacesV ofthe base andcolletwill serve to lock the tube more rigidly and securely to thecollet when desired. The instrument base may be readily vturned to seatin the collet or to be removed therefrom, or to be adjusted relative tothe collet, the base being preferably knurled as indicated at 26 toaiord a better hold.

The instrument end or point 27 is inserted in the front end of thebase24 and is hollow for receiving the electric heat element 28.

This element extends through an insulating bushing 29 in the base andone terminal of the element connects With the terminal tip 30 extendingfrom the bushing 29. The other end of the heating element connects tothe termi. nal sleeve 31 surrounding the terminal tip 30 and secured inthe end of the base 24. lVhen the tool structureisl inserted into thehandle or grip part, the terminal sleeve 31 Will en-v gage With theterminal spring 16 of the switch mechanisms within the handle, and upondepression of the button 12 the terminal spring 15 Will be brought intoelectrical contact with the terminal tip 8() so that the electric supplycircuit Will be closed through the electric heat element and thiselement will then supply the necessary heat for the tool point. Whenthel instrument structure is inserted into the handle or grip part, thesplit collet Willlhold the base of the instrument tight enough Vso that"J the instrument Will not come out nor turn as a result of any pressureapplied to it in the:

usual dental practice, and lby means of the knurling on the instrumentbasel the instru- 25 ment can bereadily turned into any position 'ldesired relative to the switchrbutton 12 on the handle. No time isWasted in applying a tool or instrument as a mere push or pullyvillserve to apply it to the handle or to remove vit 30, therefrom.

I claim as follows 1. An instrument structure of the class describedcomprisingv a handle part and an instrument part, said instrument partcom-v prising a base having an operating tool eX- tending from the outerend thereof anda shank extendingy from the inner end thereof, and acollet threaded into the end of said handle part to form a socketforreceiving Y said shank, the inner end of said collet be ing entirelyclear of the handle part wall and being split to form elastic segmentsfor clamping said shank to thereby hold said instrument part inoperativeposition. relative to the handle part.

2. In an instrument structure of the class described, the combination ofa tubular body part and an instrument part, said instrument partcomprising a base having an operating` tool extending from the outer endthereof and having a shank at its inner end, a collect' threaded 4intothe end of said tubular han'- dle part to form a receiving socket forsaid shank, the inner end of said collet being entirely spaced away fromthe handle part Wall and being split to be radially elastic,said elasticsectionof the collet receiving the outer end of said shank to hold theinstrument part in operative position relative to said handle part, theouter end of said collet being tapered and the inner endk of said shankbeing correspondingly tapered, said tapered sections interiitting; l

3.V In an instrument structure of the class described, the combinationof a tubular handle part and an instrument part comprising a base havingan operating tool at its outer end and a shank at its inner end, anelectric heating element extending through said tool and base andterminals therefor at the inner end of said shank, a collet inserted inthe end of said handle part andbeing spaced atits n` ner end entirely.avvayfrom the handle part Wall and being slitted longitudinally toprovide clamping tongues, said shank fitting into said colletto beicla'mped by said tongues, circuit terminals Within said handle part,

land a push button controlling-the operative connection of said circuitterminals With said heating element terminals, the clamping enthecombination of a tubular handle part, aV

socket member forming part ofV and secured in the open end of'saidyhandle part andv hav- ,I

ing a taperedbore, asplit skirt extending from said socket memberforming .a continuation of said ytapered `bore and being clear of thehandle part Wall t0v be radiallyyieldable,

and an instrument part comprising a base having a shank extendingtherefrom, said shank atits endbeingv cylindrical to engage in saidsplit skirt and above said end being tapered to fit the tapered bore ofsaid socket.

In Witness whereof, Ivhereunto subscribe f day of March, 1926.

my name this 29th OSCAR H. PIEPER.

ll@ Y

